Rotary pulverizer



(No Model.)

2 Sheets-Shelet 1.

R. YATBS. ROTARY PULVBRIZER.

N0..412.823. Patented 001;. 15, 1889.

HJ- fm1 ZKM@ ( No Model.)

Y 2 Sheets-Sheet 2. R. YATES.

ROTARY PULVBRIZER.

No. 412,823. Patented Oot. l5, 1889.

N. PETERS, Fhoxmthegnphu, washington, uit4 UNITED STATES PATENT OEErCE.

ROBERT YATES, OF OMAHA, NEBRASKA, ASSIGNOR TO HIMSELF, AND CHARLES KAESTNER AND FRANK A. HECHT, BOTH OF CHICAGO, ILLINOIS RQTARY PU LVERIZER.

SPECIFICATION forming part of Letters Patent No. 412,823, dated October 15, 1889.

Application filed June 7. 1888. Serial No. 276,315. (No model.)

To all whom, it may concern:

Be it known that I, ROBERT YATES, residing at Omaha, in the county of Douglas and State of Nebraska, and a citizen of the Dominion of Canada, have invented a new and useful Improvement in Rotary Pulverizers, of which the following is a specification, reference being had to the accompanying drawings, in which- Io Figure l is a front elevation.

central longitudinal section. Fig. 3 is a central cross-section. Fig. 4 is an end elevation.

The object of this invention is to overcome the difliculties heretofore experienced in the i 5 use of this class of machines, as they were liable to discharge their material in a par tially ground or pulverized state.

By the application of the improvements hereinafter described, the machine becomes a 2o crusher, pulverizer, and a complete grindingmachine, delivering only such material as has been ground to a ne powder; and its nature consists in the improvements hereinafter described, and made the subject-matter of the 2 5 claims.

In thedrawings, A indicates the base.

B B' indicate the supportingframes for the shafts; C C', the shafts; D D', the drivingpulleys; E E', cup-shaped concavo convex 3o heads; F F', containing-cylinders.

G indicates a middle nonrotating section; H, a hopper; 1', a perforated plate or screen, and .I an exhaustpipe having an enlarged section or separating-chamber K.

3 5 The machine is usually made of cast-iron, With the exception of the shafts, which maybe made of wrought-iron or steel forgings, and the exhaust-pipe with its enlarged section or separating-chamber, which may be made of sheet 4o metal.

The machine is made substantially in the form shown, giving each shaft two bearings. The headsE E', having the interior concave, are attached to the inner ends of the shafts,

and are provided with sections or cylinders F F', the inner ends of which project inward to the interior of the section G. The middle section G ismade in the form shown and of a larger diameter than the cylinders F F', as

5o shown. The section G is provided at its back Eig. 2 is a with a perforated concavoconvex plate I, through which perforations the pulverized material can pass and be exhausted out at the pipe J. This perforated plate is attached so as to be renewable when desired, and it is arranged as shown in Fig. 3, so that any frag ments escaping that are not properly pulverized or ground may drop back to it and reenter the machine Yfor further grinding; and

in order that a strong suction maybe used 6o without carrying such insuificiently-ground parts over and out of the machine the pipe J is provided with an enlarged section or separating-chamber K, for the purpose of slacking the current, so that the heavier parts may fall back into the machine and be reground. Any suitable suction or exhaust device may be applied to the end of the pipe J to withdraw the properly-pulverized material from the machine. It will be seen that the perfo- 7o rated concavoconvex plate or screen I is so arranged with the concave face inward as to assist greatly in holding the unpulverized material Within the pulverizing-chamber, while permitting the escape of the material that is sufficiently crushed to pass through its perforations. It will also be observed that the convex outer surface of this screen facilitates the passage over it of the coarser material that drops back through the exhaust-pipe. The 8c partly-crushed ores which are fed into the hopper pass out of the section G into the cyl inders F F', and when the machine is filled the rotation of the cylinders and the material contained therein by coming in contactwith the nonrotating material in the section G gives a rapid grinding and pulverizing action, which act-ion tends also to wear away the ro tating cylinders, and as they wear away they may be moved inward by moving the shafts 9o C C', so as to nearly or quite wear them out up their entire length. This action would also wear away the heads E E', if they were in a plane at right angles with the ends of the cylA inders, as the material fed into the section G assumes a somewhat conical form in the line of action between the rotating and non-rotatn ing parts, By making the heads E E' inten riorly concave they do not wear away, so that these revolving cylinders can be renewed loo Withoutrenewing the headsE E, thus making a material saving in the renewal of the parts.

In operation the material is thrown into the case through the hopper I-I and forms itself into a sold mass in the cylinders er cups and throughout the body of the central section. The cylinders or cups are revolved rapidly, and the material contain ed therein is crushed and ground against comparatively stationary materials within the section G, and as it is reduced it is thrown or drawn out through the screen I and caught by the current of air and exhausted through the pipe J, and such particles or portions of the material as are thrown or drawn through the screen and are too heavy to be carried out by the current of air will be separated in the enlargement or separating chamber K, and rolled down over the screen and through the opening at the bottom into the ease to be further ground. Two cylinders or cups give the best results when they are both rotated in the direction indicated by the arrow in Fig. 3; but it will be obvious that they may be rotated in opposite directions, if desired; and it will be 'further obvious that an operative machine may be produced by omitting one ot the rotating cylinders, so that it will be single instead of double acting; but the double-acting form shown gives the best results, although requiring more power. As shown, the parts are put together with lag-bolts; but by making the anges wider headed bolts with nuts may be used.

I am aware that pulverizing and `grinding machines have been heretofore made which embody two revolving heads or cylinders arranged opposite to each other in the general form here shown; and I do not, therefore, broadly claim them.

Vhat I claim as new, and desire to secure by Letters Patent, isl l. In a rotary pulverizer, the combination, with the pulveriziiig-chamber, the rotary cylinders F F', and the exhaust-pipe J, communicatin g with the pulverizing-chamber, of the concave-convex screen I, located between the pulverizing-chamber and the exhaust-pipe to screen the material passing from the chamber to the exhaust-pipe, said screen being terminated short of the wall of the exit-passage from said chamber to form an open channel for the Vreturn of coarse material to the chamber, substantially as described.

2. In a rotary pulverizer, the combination of the nou-rotating central section Gr, the rotary sections or cylinders F F', having concaved heads, the hopper leading into non-rotating section, the upwardly-extending exhaust-pipe J, communicating with the nonrotating section and formed with an enlarged section or separatingchamber K, and the eencavo-con vex screen I, located at the rear of the non-rotating section between it and the eX- haust-pipe, substantially as described.

ROBERT YATES. lVitnesses:

HARRY T. JONES, ROBERT A. MILLAR. 

